1. Field of the Invention
This invention relates to a device for preventing turn-around-motions of the free trolleys in a power-and-free conveyor when the free trolleys are taken off from a free rail.
2. Description of the Prior Art
A conventional power-and-free conveyor includes a power rail, a free rail provided below the power rail and a carrier which travels on the free rail. The carrier comprises a pair of front and rear free trolleys movably supported by the free rail, and a connecting link which interconnects the free trolleys. Such power-and-free conveyor transports articles such as clothes, which are hung on the carrier, in such places as distribution center, warehouse, production flow line, etc., and the carriers are taken off from and put on the free rail by a worker in many places of a conveyor line. On the other hand, the opposite ends of the connecting link are horizontally pivotally connected to the free trolleys and the free trolleys can freely turn or swing around in any direction in a horizontal plane, thus enabling the carrier to travel along the curved portion of the rails. This construction causes the situation that the directions of the free trolleys are different from each other and also from the direction in which the connecting link extends, when the carriers are taken off from the free rail. Accordingly, to position the carrier on the free rail, it is necessary to put the trolleys in the same direction as that of the connecting link. Righting the direction of the free trolleys requires much trouble and lowers efficiency of the works such as taking off and putting on the carriers, introducing the carriers into the conveyor line, exchanging the carriers, etc.